Unfolding Onshape Sheet Metal
Sheet metal is one of those materials that is so versatile it can be used for almost any application. It’s lightweight, inexpensive, and easily formed into almost any shape. However, for all its versatility, it is usually confined to the very mundane task of providing the world with cases, covers, and brackets. But without these, where would we be? Moldings, castings and machining from solid are way too expensive. So for many applications, sheet metal is the go-to material and manufacturing process.
Designing a sheet metal part in 3D has its own challenges. Not only do you have to model each individual wall, flange, bend, bend relief, and corner, but you also have to make sure it can actually be manufactured. Will it unfold? Do any of the flattened walls collide? Is it using the correct bend allowance?
Sheet metal lives by its own rules and that’s why many traditional desktop-installed CAD applications have a specific sheet metal module, mode, or add-in to help you build these unique parts (with varying degrees of success). These sheet metal tools are often in a completely different environment to the normal design tools, so you have to rely heavily on manual measurements or in-context assembly design to make sure your sheet metal parts are fit for purpose.
However, the biggest challenge is collaboration with manufacturing. As a designer, you may think your sheet metal part looks great and that it unfolds nicely, but your manufacturing counterpart has different ideas (I have firsthand experience of this). Unless you are the same person who designs and manufactures the sheet metal parts in-house, there will always be a disconnect between the two teams. And if you’re not under the same roof, it’s even worse.
So what does this have to do with Onshape?
Yesterday, we announced our soon-to-be-released sheet metal design tools. We call it Simultaneous Sheet Metal. Why? Because the unique full-cloud architecture of Onshape, that enables parallel processing and true real-time collaboration between teams, also lends itself perfectly to sheet metal design.
Every team member from every discipline can see everything they need to see, simultaneously. There is no sheet metal mode. There is no folded or flat mode. There is no bend table mode. All the data you need is calculated and displayed at the same time and is always in sync. Everyone can see, edit, and inspect the design from the first initial concept right through to finished product, so there are no surprises along the way. This is true Agile Design. You can visualize errors and interferences immediately, consider alternatives quickly and ultimately, reduce scrap and wasted time.
How Onshape tackles sheet metal design
Multi-part Part Studios are already a great way to design subassemblies or entire products, together in one environment, to ensure that all parts fit together perfectly. With the addition of sheet metal design tools, Part Studios are now even more powerful.
As mentioned earlier, there is no sheet metal mode. When you need to create a sheet metal part, rather than use the regular solid modeling tools, simply press the “Sheet metal model” icon:
This new feature lets you define your material thickness, bend radius and K Factor as well as your default corner and bend reliefs. Any subsequent features that are added to this sheet metal part, like flanges, will use this default behavior. You can then start your sheet metal model using one of three different methods depending upon your application:
- Convert a Solid – If you need to create a sheet metal enclosure, this is the perfect solution and in many cases (pun intended) it is the fastest and most practical way to create a sheet metal part. First create a solid volume that encloses your design, then specify which faces of the solid should become walls and which edges should become bends.
- Extrude a Sketch – To create a channel, complete with bends at each vertex.
- Thicken a Face – A face can be a solid face, a surface, or an enclosed sketch. For example, you can use a face from another part to define a flange for a bracket that connects two parts together, or you can use a sketch to define a panel layout to position components in your assembly.
Complex sheet metal parts can be created quickly and easily by converting a solid that represents the space envelope of the area you want to enclose.
As soon as you create a sheet metal model feature in your Part Studio, a tab appears on the right hand side of the graphics area. Click the tab and the flat view and bend table are shown even before you have finished creating your first feature. This allows you to check for collisions as you decide which edges to bend and is already saving you time and reducing potential errors.
You can keep the flat view and bend table open as you design. Add flanges, partial flanges, or cuts across bends and you will see the immediate effect on your flat pattern. You can also edit bend order, convert bends to rips and vice versa, and modify individual bend radii all from the bend table. This means that you don't have to keep bouncing back and forth between a folded view and a flat view every time you make a change (like you have to in traditional CAD). If you share your Document with manufacturing, they can make these changes for you to suit available tooling or manufacturing methods.
The bend table and flat view panel provides simultaneous viewing and editing capabilities while designing your sheet metal parts.
Flanges can be easily created by selecting one or more edges and defining size, direction and angle. Any flanges that interfere with each other are automatically mitered and corner conditions or bend reliefs automatically added. To create a partial flange, use the Move Face feature, which knows you are editing a sheet metal part and automatically adds bend reliefs.
When you’ve finished adding flanges to your sheet metal part, you can then add any features that don’t need to appear in the flat pattern – like forms, louvers, and welds. These features can be added manually, by deriving them from another Part Studio or Document, or by using a custom FeatureScript feature. And finally, you can also create a drawing of the flattened part and add dimensions for manufacturing if required.
Move Face automatically adds bend reliefs to create partial flanges.
Building your parts together in a Part Studio has many advantages. Soon you will also be able to develop multiple sheet metal parts with different material properties together in a single Part Studio. Couple these capabilities with in-context assembly design and you’ve got a winning combination!
Simultaneous Sheet Metal is now available in Onshape. If you want to see an overview of Sheet Metal, please watch this video.